1. Field
Apparatuses and methods consistent with the exemplary embodiments of the inventive concept relate to a method of determining reserved tones and a transmitter performing peak to average power ratio (PAPR) reduction using tone reservation, and more particularly, to a transmitter determining carrier indices reserved for PAPR reduction and performing PAPR reduction using tone reservation.
2. Description of the Related Art
Recently, broadcast and communication services become multi-functional and wideband high quality. Also, in accordance with the development of electronic technologies, various broadcast receiving devices such as a high-definition digital television, a high specification smartphone, and the like have been introduced and increasingly used. As a result, the demand on various receiving methods and various service supports for broadcast services has been increased.
Meanwhile, many transmitting and receiving systems provide broadcast services through an Orthogonal Frequency Division Multiplexing (OFDM) scheme. Since the OFDM scheme performs data transmission using a plurality of carriers (or sub-carriers) in a predetermined frequency band, it may transmit data at high speed and has characteristics that it is strong against multipath fading.
However, in the OFDM scheme, a transmission signal occasionally has a large peak-to-average power ratio (PAPR). Data is transmitted through multi-carriers by performing Inverse Fast Fourier Transform (IFFT) on a signal of a frequency domain. Here, a size of an amplitude of an OFDM signal may be represented by a sum of amplitudes of the multi-carriers. Therefore, in the case where phases of the multi-carriers are the same, an OFDM signal having a high maximum value is generated, which represents a very high PAPR.
An OFDM signal having a very high PAPR deteriorates efficiency of a high power amplifier and the high power amplifier is operated in a non-linear region out of a linear operation range thereof, and thus, the OFDM signal is distorted. Accordingly, there is a problem that performance of a transmission and/or reception system is degraded. As a result, research into a method for reducing the PAPR is requested.